Microelectronic imaging devices are used in a multitude of electronic devices. As microelectronic imaging devices have decreased in size and improvements have been made with respect to image quality and resolution, they are now commonly found in electronic devices including mobile telephones and personal digital assistants (PDAs) in addition to their traditional uses in digital cameras.
Microelectronic imaging devices include image sensors that typically are charged coupled device (CCD) systems or complementary metal-oxide semiconductor (CMOS) systems, as well as other imaging technologies. The lenses for these microelectronic imaging devices may require mobility for operations such as automatic focus or zoom features. To meet the increased need for smaller lenses with retained mobility, MEMS structures have been incorporated into lens stacks. For example, MEMS wafers may be integrated with lenses to be used as, e.g., an automatic focus (autofocus) or zoom system by accurately changing the relative distance of the lenses with respect to each other and/or a pixel array.
MEMS is a relatively new technology that exploits the existing microelectronics infrastructure to create complex machines with micron feature sizes. MEMS structures have been created for lens movement and may be integrated with lenses. Some examples of MEMS structures which my be used for lens movement may be found in U.S. Pat. Nos. 6,636,653, 7,242,541 and 7,280,290.
Lens replication for imaging devices may be carried out on a glass wafer using an ultra-violet (UV) curable optical polymer and a compression stamp or mold. Processes for manufacturing imaging devices which include lens structures and MEMS structures for moving the lens structures can be expensive because the MEMS structures and lenses are created in separated processes, and then attached together in a subsequent process. Bulky mechanical packaging is another problem experienced with the lens/MEMS structure combination. There is a need for a more efficient, less bulky and less expensive method of forming lenses which are integrated with MEMS structures.